DE1576089A1 - Power amplifier or servo motor - Google Patents

Description

Power amplifier or servo motor. (Addition to patent ....... patent application -6- 50 Q9Q ~ Ia / 60)

The invention relates to improvements to with With the help of a pressure medium to be actuated power amplifiers or servomotors of the type with which energy or a Force is generated by being under the controlling influence of Yentilmittel different fluid pressures "to the effect be brought to the opposite side of a movable wall.

Such power boosters are used, for example, in the braking systems of vehicles, the mentioned pressure difference between the pressure of the atmosphere and the pressure prevailing in a negative pressure source, e.g. the negative pressure in the intake line of a vehicle engine, or between a compressed air source and the atmosphere. .

'In claim 1 of patent a ............ (patent application

G 39 890 la / 60) speaks of a power booster that can be actuated with the aid of a pressure medium and that has a housing

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further comprises a force introduction member which is via a lever in the housing acts on a force output member, a wall arranged in the housing on which the lever acts, the Wall can be moved in dependence on a pressure difference in order to increase the effect of the force introduced on the force output member amplify, as well as valve means which regulate the development of the pressure difference, these valve means at a Movement of the force introduction organ are actuated; this The booster is characterized in that the movable wall acts on the lever at a first point that corresponds to the The center of pressure of the movable wall coincides that the Force introduction member acts on the lever at a second point, and that the lever at one between the first and the second point lying point is pivotably mounted about a bearing, which through the point of attack between the lever and the force output member is formed.

The present invention now provides a power booster to be actuated with the aid of a pressure medium according to claim 1 of the above-mentioned patent, which is characterized in that the force-introducing element and the force-output element are arranged coaxially on the axis of the force booster, and the lever by a part the movable wall is formed and angular movements can perform a storage on a different Eeil the movable wall, said bearing is arranged at a distance from the Aohae of Kraftverstarkers.

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In one embodiment, the lever comprises a carrier or eiiiG plate that is supported by a membrane or forms part of a membrane, one side of which is constantly exposed to a constant pressure, while the other side is subjected to the prevailing in the power amplifier's control kaiiinier

Is exposed to pressure. ■

The force introduction element engages on the plate or the carrier at a point which is on the abandoned from storage Side of the pressure center of the membrane is.

The plate or the support can be supported by a weak spring be biased,. which strives to the plate or the To move the carrier in a Bichtung which is opposite to the Bichtung in which this component by the actuator is moved. ·

If the booster is operated, the lever performs a Pivoting movement about the mentioned bearing au3 and brings a reaction or "feeling" force on the force introduction member which counteracts the force applied to this organ; this is where this action or "feeling" force is directed according to the size of the pressure difference acting on the movable wall.

The invention is illustrated more schematically below with reference to the hand Drawings of several exemplary embodiments explained in more detail.

Fig. 1 shows in longitudinal section "a booster type supported by a vacuum. '■

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FIG. 2 is a perspective view of a mounting that can be used in the booster according to FIG. 1.

Fig. 3 is a longitudinal section through a further embodiment a booster which is operated by a negative pressure supported design.

Fig. 4 shows in a section along the line 4-4 in 3 shows a vacuum valve.

"FIG. 5 is a cross-sectional view taken along line 5-5 in FIG. 2. FIG. 6 is a section taken along line 6-6 in FIG. 5.

The booster shown in Fig. 1 comprises a housing or a cylinder 10, which through a movable wall 13 into a front chamber 11 exposed to constant pressure and a rear power actuation chamber 12 is divided. The movable wall may comprise a piston operating in the cylinder 10, or it is constituted by a rigid one as shown in FIG. 1 "Piston 14 is formed, with a significant margin between the circumferential surface of the piston and the cylinder wall of the housing is present, with which the piston has a sealing effect is connected by a rolling diaphragm 15.

Furthermore, an actuating member 16 is provided, which is a rod which can be actuated via a pedal; the inner end of the rod 16 arranged on the axis of the housing or cylinder carries an annular member 17 rotatably connected thereto, which in turn supports a carrier or a plate 18 which forms part of the

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movable wall 13 forms.

The rpräger 18 has a generally circular outline and is arranged eccentrically to the axis of the booster, the center of pressure of the beam between the axis of the Force amplifier and a point near the circumferential surface of the piston 14 is located. One acting as a sealing organ Rolling membrane 19, through which the carrier is supported, connects the band of the 3 carrier with the back of the piston 14. An its radially outermost circumferential point the carrier is biased against the piston 14 by a spring 20, and at a point between the center of pressure of the diaphragm 19 and the axis of the force introduction member 17 is located, the carrier can execute pivoting movements about a bearing 21 on the rear side of the piston 14.

A bing channel 22 is located in the annular component 17 with the chamber 11 via an opening 23 of the piston 14 and a Opening 24 in the carrier 18 in connection. The bing channel 22 is further connected to the chamber 12 through an opening 25 of the carrier connected, which is controlled by a vacuum valve 26, the with an annular slot 27 on the periphery of the opening 25 cooperates on the front of the wearer. The valve organ 26 is coupled to an air valve member 28 which the Connection ^ between an annular chamber 29 in the piston 14 and the chamber 12 via an opening 30 controls. The valve organ 28 normally selected by a spring 31 attached a valve seat held on the circumference of the opening 30 "

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Furthermore, a rod 32 with an axial bore 33 is provided coaxially with the force introduction member 16 as a force output member. The force output member 32 is axially movably guided by a Ftihrungsteil 34 \ in an annular recess of the guide part 34 is a gasket 35 is disposed. The hearing part is attached to the front end wall 36 of the housing 10.

The power output element actuates a piston 37 of a master cylinder 38, with which the booster can be united. At its rear end, the power delivery member is from a Opening added to the front of the piston 14, and the axial bore 33 communicates with chamber 99 in piston 14 Link.

In the boo position or the "equilibrium" position of the booster, stops 39 on the back of the piston H are brought into contact with the rear by a return spring 40 End wall of the housing 10 held. The spring 20 biases the carrier 18 against the sighting in which it is moved by the force introduction member 16, so that the carrier rests against a stop 41 on the piston 14. In this position, the carrier 18 is from the vacuum valve member 26 ' lifted off, so that the connected to a vacuum source Chamber 11 via the openings 23 and 24, the hanging channel 22 and the opening 25 is connected to the chamber 12.

If the booster is to be operated, it will Force introduction member 16, which is through a rolling diaphragm 42 and a

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Cuff 43 is sealed, actuated to the carrier 18 around to pivot the bearing 21 in such a direction that the Unterdrucicventil 26, 27 closed and the actuation chamber 12 of the booster opposite the ink he shut off pressure source will. With a further movement of the carrier 18 the air valve 28 is opened so that air can enter the actuating chamber via an air filter 45 and the bore 33 of the power delivery rod 32 can flow in, the pressure difference acting on the membrane 19 exerting a force on the carrier 18, which strives to pivot the carrier about the bearing 21 against the Bichtung with which it is through the force introduction member 16 can be moved. When the pressure increases, will the carrier 18 returned to a position in which the Air valve '28 closes and the system equilibrates is maintained until the force applied by the force introduction member 16 to the carrier 1 & is increased or decreased ' will.

Regarding the pressure difference on the carrier applied force can be assumed to be on the center of pressure the membrane 19 acts, and that the force amplification ratio, i.e. the ratio between the force applied by the organ 16 and that by the force amplifier generated force according to the distances between the points of application of this Forces from the storage 21 directs. ·

Characterized - that the location of the storage 21 relative to the Carrier 18 changes, one can thus change the power amplification ratio as desired without any other changes

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Parts of the device need to be modified.

The bearing 21 can be formed, for example, by a projection 46 of a base part 47 which can be removed from a Recess 48 of the piston 14 is received, and you can have several such bearing parts for a booster Provide similar base sections, in which, however, the projections or bearings are at different points along the length of the base part are arranged so that the power amplifier * can change ratio by either pivoting the existing bearing part by 180 ° as shown in FIG. 2 or one other bearing part is installed.

When the power amplifier is operated, a reaction or "feel" force via the bracket 18 to the pedal transferred back, with this force being the ~ line member 16 counteracts applied pedal force. The size of this reaction force is proportional to the size of the pressure difference occurring on the membrane 19.

In the event of failure of the booster, the on the force introduction member 16 applied force via the Carrier 18 can be transferred to piston 14 and from there to power output element 32.

The power amplifier according to the invention shown in FIGS. 3 to 6 comprises a housing or cylinder 50 which is composed of two generally cup-shaped components 51 and 52, between which the outer band 53 of a flexible

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Membrane54 is clamped. This membrane forms a part a total of 55 designated movable wall that divides the interior of the housing or cylinder 50 into a front, one constant pressure chamber 56 and a rear Actuating chamber 57 divided. The diaphragm 54 is offset radially inward on one of its outer bands Place clamped between two plate-shaped pressed parts 58 and 59, the bridges are arranged on bridges and form the piston of the booster. Within a circular pia- ■ before 60 of considerable size, the- eccentric to the axis of the Power booster is arranged, the pressing parts 58 and 59 are provided with complementary depressions that differ from the Membrane extend away, and a circular part 61 of the membrane between the circular recesses of the pressing parts is located by a lever in the form of a circular beam or a plate 62 is supported. Nearest to the farthest radially the outer point of its band, the carrier 62 is biased by a spring 63 in the direction of the pressing part 58. At a point lying between the pressure center point of the part 61 of the diaphragm and the axis of the force amplifier, the Carrier 62 carry out pivoting movements around a bearing on the back of the press part 58 »This bearing can be carried out by a» zig component are formed, which is based on the diameter of the circular surface 60 of the pressed part, which runs through the axis of the booster, but includes the storage preferably two pins or tenons 63 'which have hemispherical heads according to FIG

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engage hemispherical pans 65 of the carrier 62. the Pins 3ind are firmly built into the pressing part 58 and are equally wide on opposite sides of the aforementioned diameter arranged by this Durohmesser; furthermore, the pins are equidistant from the axis of the force amplifier.

The membrane 54 carries on its inner band a bead or Hing 66 between the front end of a sleeve 67, the a control valve unit for the booster receives, and a component 68 is clamped, which at its front end carries a port set 69 which engages the carrier 62 at a point lying on the axis of the booster. the The axis of the sleeve 67 lies on the axis of the booster, and the sleeve is slidable in a seal 70 formed in an annular recess. 71 in a rear extension 72 of the housing part 52 is arranged.

A force introduction element 73, which is formed, for example, as a rod from -P which can be actuated by a pedal, is arranged on the axis of the force amplifier, and the inner end of this component engages a component 74 screwed into the sleeve 67. A flexible sleeve 75 connects the outer end of the sleeve 67 with the extension 72 of the housing ^ - part 52 and protects the seal 70 against contamination; In addition, the penetration of dirt and other foreign bodies into the sleeve is prevented by a filter 76 through which air can enter and through the central opening of which the

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Force introduction member 73 extends

A valve member in the form of a piston valve 77 is -im inner end of the sleeve 67 is arranged near the component 68 and is held in position in the sleeve by a pin 78, which looks perpendicular to the axis of the booster and protrudes through an opening 79 of the piston valve 77; a sealing ring 80 is through the piston valve on its inner end and beyond the pin 78 supports to a. To effect sealing between the relevant part of the piston valve and the sleeve. The pin 78 protrudes at its ends through diametrically opposed axial slots 81 and 82 in the wall of the sleeve 67, and the outer ends of the The pin will have diametrically opposed holes "85 in a rearwardly projecting tubular extension 84 of the pressing part 59 was added. Here, the arrangement is such that the sleeve 67 and the pin 78 are in the axial Can move sighting relative to each other along a route, which is determined by the length of the slots 81 and 82. In the sleeve is between the rear end of the spool and the component 74, a valve member 85 is arranged, which normally by a spring 86 against a bing shoulder 87 of the sleeve 67 is biased, which forms a valve seat.

The chambers 56 and 57 on either side of the movable Wall stand over the valve assembly housed in the sleeve 67 in connection. Typically, the chamber 56 is connected to a suitable source of negative pressure, such as the

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Intake line of a vehicle engine ·, and for this purpose is • A connection not shown here is provided.

In the boo state "or" in the "equilibrium" position the shell 67 and the movable wall 55 become complete held retracted position, namely by a BüQkfUhrfeder 88, which eioh between the housing part 51 and a plate 89 arranged on the pressing part 60 is supported, wherein the movable wall rests against the housing part 52. The front ends of the slots 81 and 82 of the sleeve 67 engage the pin 78, and the piston valve 77 is held at a distance from the valve member 85. Here is the Chamber 56 with chamber 57 via an opening 90 in the pressed part 58 in connection, this opening with openings 91 and 92 in the carrier 62 or the component 68 and two parallel Channels 93 communicates through the spool 77 «· A tree 94 between the piston valve 77 and the valve element 85 stands with the chamber 57 above the Slot · 81 and 82 of the sleeve 67 and openings in the tubular Approach 84 of the pressing part 59 in connection. The part 61 lying between the circular surfaces of the two pressed parts of the membrane is through an opening 95.dee pressing parts 59 to the in the chamber 57 is exposed to the prevailing pressure. In the aforementioned boon or equality position, the chambers 56 and 57 connected to each other and therefore both exposed to the negative pressure.

_v If the booster is to be operated, this will

Force introduction member 73 moved so that the Hülae 67 forward

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is moved in order to bring the valve element 85 to abut the piston "slide 77" and to shut off the actuating chamber 57 of the force amplifier from the vacuum source further movement of the sleeve, the valve member 85 is lifted from its seat 87 within the sleeve 67, so that air via the air filter 76 and a channel 96 of the component 74 past the valve seat 87 and via the slots 83 and the openings in the flange 84 in can flow in the actuating chamber 57th same time, the lever is pivoted further in the clockwise direction 62, and the resultant force, which during cooperation dee extension 69 with the lever 62 and the actuation of the movable wall yields to the pressure difference, is Winem force output member in the form of a rod 97. The rod 97 is on the axis of the power amplifier and coaxial with the force introduction "organ 73 arranged i the rod 97 actuates the piston of a hydraulic master cylinder, as has already been described with respect to the embodiment according to FIGS. ;

A force created by the pressure difference across that part of the diaphragm ^; is applied between the circular surfaces of the Preßtsile 58 and 59, engages substantially at the bridge center point of the membrane part 61 and strives to sohwenken the lever 62 anticlockwise about its bearing 64, so that a reaction or "feeling" on the pedal "-Force

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PATENT CLAIM]

j Dr. lixpl.

1;. With the help of a pressure medium to be actuated power amplifier according to the first claim 4th patent * (... ··· .......... · Patent application Q 39 890 Ia / 60) _f . characterized in that the force introduction member and the force output member are coaxially arranged and the lever is formed by a part of the movable wall and "o is mounted" that it can perform angular movements around a mounting on another part of the movable, this mounting in one Distance from the axis of the booster is arranged.

2. Booster according to claim 1, characterized in that the lever has a carrier or a plate which is supported by a membrane or forms part of a membrane, one side of which is constantly a constant Pressure is applied while the other side of the Membrane that is in an actuation chamber of the booster is exposed to prevailing pressure

3 «booster according to claim 2, characterized in that the carrier or the plate with the Force introduction organ cooperates at a point on the side facing away from the bearing of the center of pressure the membrane lies.

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Claims (1)

- 14 - ■ · ■ - ■ · IjM ^ Q- 767 applied to the force applied via the sleeve ' counteracts. The magnitude of this reactive or "feeling" force is proportional to the size of the pressure difference which comes into effect on the part 61 of the membrane on which there is the lever 62 supports ·, -'- ■ " Claims: ■ - 16 - "1A-30 767 4. Booster according to claim 3, characterized in that the carrier or the plate by a leather is biased, which biases the carrier or the plate opposite to the direction in which the plate or the carrier is moved by the force introduction member. 5. Booster according to claim 3 or 4, characterized in that on the carrier or the plate at a point that is on the soap applied from storage te of the pressure center point of the diaphragm one to be actuated by a pedal, arranged coaxially with the booster Can attack the bumper, so that when the power amplifier is actuated, the carrier or the plate is pivoted around the bearing becomes and a reaction or "feeling" force on the pedal applies, which is after occurring on the membrane Pressure difference. 6. booster according to claim 1 to 5, characterized g e mark t that the lever does the actuation 'The valve controlling the force amplifier is actuated. 7. Booster according to claim 1, characterized in that the movable wall comprises a piston, being between the outer band of the piston and one in the. The circumferential direction of the wall of the housing of the booster has a considerable margin, with the Piston with the housing through a first acting as a seal. ' Wälimembran is connected, wherein a generally circular support or a plate, which or which forms the lever, eccentric 20 98 11/039 2 ■ - 17 - .1A-30 767 tric to the axis of the power amplifier on the power input line organ is arranged adjacent side of the piston, a second membrane providing a seal between the tape of the carrier or the plate and the mentioned side of the piston causes one side of the second diaphragm to be constantly exposed to a constant pressure via an opening in the piston is, and wherein the other side of the second membrane corresponds to the in an actuation chamber of the booster is exposed to prevailing pressure. ■ 8. booster according to claim 1, characterized in that the movable wall comprises a piston, wherein between the outer band of the piston and a circumferentially extending wall of the housing of the booster there is considerable leeway, the piston comprising two components which are circular within a Area of considerable size, which is opposite to the axis of the ' Booster is offset and arranged eccentrically to it, are deformed so that they are in the area of this surface by a " Spaced apart, with a generally circular beam or plate that forms the lever attached to the deformed Sections arranged between the two components of the piston is, with a membrane between the two components is clamped and a seal between the band of the piston and the circumferential sand of the Housing causes, the zwisohen the deformed circular Sections of the two components lying part of the membrane 2 0 9811/0392 original i - 18 - 1A-30 767 by, the plate or the carrier is supported, with a Side of the section of the membrane lying between the two components via an opening in the component adjacent to it the piston is constantly exposed to a constant pressure i3t, and wherein the other side of the part of the membrane lying between the two components corresponds to that in an actuation chamber of the Booster is exposed to the prevailing pressure. 9. booster according to claim 8, characterized geke η η - ψ is characterized in that the two components are formed by fiücken arranged to back dish-shaped pressed parts. 509811/0392 _BAD